XML 188 R160.htm IDEA: XBRL DOCUMENT
v3.20.4

Exchangeable Securities - Schedule of Exchangeable Securities (Details) - CAD ($) $ in Millions | Dec. 31, 2020 | Oct. 22, 2020 | Dec. 31, 2019 | May 01, 2019 | Jul. 20, 2018
--- | --- | --- | --- | --- | ---
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Interest rate |  | 4.07% |  |  | 4.509%
Credit facilities, long-term debt, and finance lease obligations | $ 3,256 |  | $ 2,699 |  |
7% Unsecured Subordinated Debentures Due May 1, 2039 |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Notes and debentures issued | $ 350 |  | $ 350 |  |
Interest rate | 7.00% |  | 7.00% | 7.00% |
Exchangeable Preferred Shares | $ 400 |  | $ 0 |  |
Credit facilities, long-term debt, and finance lease obligations | 750 |  | 350 |  |
Gross carrying amount | 7% Unsecured Subordinated Debentures Due May 1, 2039 |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Notes and debentures issued | 330 |  | 326 |  |
Exchangeable Preferred Shares | 400 |  | 0 |  |
Credit facilities, long-term debt, and finance lease obligations | $ 730 |  | $ 326 |  |

X
- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_7&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsInterestRate
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The non-current portion of non-current borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_LongtermBorrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of notes and debentures issued by the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_NotesAndDebenturesIssued
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Exchangeable Preferred Shares + References No definition available. + Details
Name: | tac_ExchangeablePreferredShares
Namespace Prefix: | tac_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=tac_SevenPercentUnsecuredSubordinatedDebenturesDueMay12039Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_GrossCarryingAmountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |